Interfacial Effect of Oxygen-Doped Nanodiamond on CuO and Micropyramidal Silicon Heterostructures for Efficient Nonenzymatic Glucose Sensor.

Herein, the novel strategy of copper oxide (CuO) deposited oxygen-doped nitrogen incorporated nanodiamond (NOND)/Si pyramids (Pyr-Si) heterostructure is studied for high-performance nonenzymatic glucose sensor. The combined properties of surface-modified NOND/Pyr-Si induced by different growth durations (5 to 20 min) of CuO is envisioned to improve glucose sensitivity and stability. For comparison, the same methods and parameters were deposited on the plane silicon wafers. The systematic analysis reveals the best glucose sensing properties of 15 min grown CuO/NOND/Pyr-Si based sensor, with a high sensitivity of 1993 μA mM cm, a lower limit of detection of 0.1 μm, and a longer stability of 28 d (∼96%). In addition, the present sensor exhibits good selectivity of glucose among other analytes such as sodium chloride, ascorbic acid, uric acid, and so on. The enhancement in glucose sensing performances of the as-fabricated CuO/NOND/Pyr-Si is ascribed to the interfacial effect of NOND and the synergistic effect of CuO and NOND/Pyr-Si. Moreover, the oxygen dopant in NOND and CuO stimulates the reactive oxygen species while measuring glucose and affords rapid recovery (<2 s). This promotes fast electron kinetics in the electrocatalytic solutions, which enhances the electroactive area and thereby contributes to a high sensitivity. These salient results suggested that the as-fabricated CuO/NOND/Pyr-Si sensor is more suitable for high-performance biosensors and effective energy storage device applications.